Auto glass grinding and edging machines



April 30, 1957 w. o. SAMSON 2,790,271

AUTO GLASS GRINDING AND EDGING MACHINES Filed Jan. 20, 1955 INVENTOR AUTO GLASS GRINDING AND EDGING MACHINES Walter O. Samson, Winnipeg, Manitoba, Canada, assignor to Pilkington Brothers (Canada) Limited, Toronto, Ontario, Canada v I Application January 20, 1955, Serial No. 483,156 1 1 Claim. (11. 51-72 My invention relates to new and useful improvements in grinding machines for the edges of auto glass and the like, the principal object and essence of my invention is to provide a device of the character herewithin described which eliminates vibration between the grinding surface and the edge of the glass thereby eliminating the chipping or cracking of the edge.

Another object of my invention is to provide a device of the character herewithin described in which the grinding surface is kept lubricated by water which not only facilitates the grinding process but washes away the ground glass coming from the edgeof the glass being ground.

Still another object of my invention is to provide a device of the character herewithin described in which the grinding surface is resilient, said resiliency being adaptable within limits by the pneumatic tire upon which the grinding belt is mounted.

A still further object of my invention is to provide a device of the character herewithin described in which the grinding belt can be removed and replaced rapidly.

Yet another object of my invention is to provide a device of the character herewithin described which is extremely simple in construction, economical in manufacture, and otherwise well suited to the purpose for which it is designed.

With the foregoing objects in view, and such other objects and advantages as will become apparent to those skilled in the art to which this invention relates as this specification proceeds, my invention consists essentially in the arrangement and construction of parts all as hereinafter more particularly described, reference being had to the accompanying drawings in which:

Figure l is a top plan view of my device.

Figure 2 is a side elevation thereof but in a slightly reduced scale.

Figure 3 is a partial section of my device substantially along the lines 3-3 of Figure 1.

Figure 4 is a sectional elevation reduced in size substantially along the lines 44 of Figure 1.

In the drawings like characters of reference indicate corresponding parts in the different figures.

Present day Window glass for automobiles requires the top and side edges thereof to be ground smooth as they are unprotected when in use and the conventional method of accomplishing this is to grind the edges upon a grindstone lubricated with water or the like.

However due to the extreme hardness of the grindstone and the inherent brittleness of window glass, particularly safety glass, the slightest jarring causes splinters to form on the edge being ground with the result that a relatively large amount of window glass is wasted during the grinding process. By this is meant that the checking or splintering usually extends beyond the limits of the grinding process and therefore the piece of glass has to be thrown away.

By providing a resilient grinding surface, I eliminate this fault thereby not only getting an improved edge upon the glass but also, and perhaps more important, providing 2 a considerable saving in cost as it is well known that the ultimate price of a sheet of glass to the consumer includes a considerable percentage for breakage and wastage.

Proceeding therefore to describe my invention in detail it will be seen upon reference to the accompanying drawings that I have provided a substantially rectangular base 1 upon which is mounted asource of power in-the form of an electric motor 2; A pulley 3 is driven by the electric motor and around this pulley a V-belt 4 extends to a further pulley 5 securedgto a drive shaft 6 situated ad-L jacent the'rear edge 7 of the base. This drive shaft is mounted for rotation within bearings'S supported upon blocks 9 which in turn are secured to the base by conventional means (not illustrated).

In this embodiment I have provided a pair of grinding i heads collectively designated 9 it beingunderstood that one of the grinding heads is for coarse grindingand the other for fine or finishing grinding but as they are identical in construction with the exception of the grit used, only one will be described.

The'bearings 8 are situated adjacent the pulley Swith heads 10 extending upwardly upon either side.

Each grinding head consists of a hub 11 recessed as at pneumatic tire 13 is secured by the inner surface 14.there-' of to the surface of the hub byfmeans of an adhesive (not illustrated) and an inflation valve 15' extends through the hub to the recess 12 and communicates with the interior of the tire so that the tire can be inflated by the valve 15.

An abrasive belt 16 carrying abrasive 17 upon the outer surface thereof is placed over the tire 13 and, when the tire is inflated, the belt is held firmly thereon by the pneumatic pressure and is therefore revolved by the hub 11.

From the foregoing it will be appreciated that the surface 17 of the abrasive belt is substantially resilient due to the fact that it is mounted upon the pneumatic tire and furthermore the degree of resiliency can be controlled within limits by varying the pressure within the tire.

A watertight casing or boxing 18 open at the upper side 19 thereof surrounds each grinding head, a portion 20 of the outer side of the boxing being slidably removable to provide access for the inflating valve 15. Conduits 21 communicate with the boxing and converge to a T- union 22 which is adapted to be connected to a source of water pressure so that water can be introduced into the boxing and onto the surface of the abrasive belt. In this connection taps 23 are provided adjacent each boxing in order to control the amount of water passing through the conduits 21.

It will be noted that the inner ends or nozzles 24 of the conduits are adapted to direct the stream of water onto the surface of the belt but in order to prevent too much water collecting within the boxing 18, drain conduits 25 are provided adjacent the rear walls 26 of the boxes, it being understood that these drain conduits can be connected by rubber tubing (not illustrated) to a convenient disposal means.

The water impinging upon the surface of the abrasive belt not only supplies lubrication during the grinding process but also washes away the ground glass dust and prevents it from contaminating the surrounding air and in order to maintain the belt in a fairly clean condition during the operation of the machine, the water should impinge upon the belt with a fair velocity and it is for this reason that the drain conduits 25 are necessary. However even with the drain conduits 25 there is a tendency for the water to be picked up by the surface of the belt, which revolves in the direction of arrow 26,

Patented :Apr." so, 1957 and due to the speed of rotation, the water is flung by centrifugal force exterially of the boxes.

I therefore provide means to wipe the surface of the belt as it leaves the boxing said means taking the form of a metal U-shaped clip 27 adapted to slip over the rear wall 26 of the boxing and spanning same, said clip having secured therein a relatively narrow base portion of a tapered sponge 28 the relatively wide head portion 29 of which engages the surface of the abrasive belt 17 as clearly shown in the accompanying drawings. It will be noted that the sides of the sponge are concave and that the contracting side thereof contacts the abrasive surface adjacent the upper end of the side thus leaving an enclosed area between the abrasive surface and the side of the sponge, which allows the surplus water and dust to be deposited within the boxing and eliminates excessive moisture being collected by the sponge.

In operation, the electric motor 2 revolves the grinding heads in the direction of arrow 26 whereupon the edge of the glass being ground is olfered to the exposed surface of the abrasive belt and due to the resiliency existing on the surface of the belt, the edge may be ground safely without shattering or chipping occurring.

Since various modifications can be made in my invention as hereinabove described, and many apparently widely different embodiments of same'made within the spirit and scope of the claim without departing from such spirit and scope, it is intended that all matter contained in the accompanying specification shall be interpreted as illustrative only and not in a limiting sense.

What I claim as my invention is:

In a glass grinding machine, the combination of a watertight casing having an open top and including front and rear walls and a pair of side walls, a power-driven shaft extending between said side walls, an abrading wheel secured to said shaft and having its upper portion projecting through the open top of the casing, a nozzle mounted in the front wall of the casing substantially at right angles to said shaft and adapted to deliver a stream of liquid perpendicularly against the periphery of said wheel, a substantially U-shaped clip secured to the upper edge of the rear wall of the casing, a tapered sponge having a relatively narrow base portion secured in said clip and a relatively wide head portion frictionally engaging the periphery of said wheel whereby to wipe excess liquid therefrom, and a water drain provided in the bottom portion of said casing.

References Cited in the file of this patent UNITED STATES PATENTS 136,939 Richardson Mar. 18, 1873 385,666 Hadley July 3, 1888 443,572 Goeldner Dec. 30, 1890 522,918 Range July 10, 1894 537,411 Fisher et al. Apr. 9, 1895 597,235 Brann Jan. 11, 1898 838,556 Lutter et al. Dec. 18, 1906 1,130,352 Tkach Mar. 2, 1915 1,487,256 Mall Mar. 18, 1924 1,715,574 Skriba June 4, 1929 2,292,229 Krueger Aug. 4, 1942 2,490,472 Raske Dec. 6, 1949 2,601,048 Monger June 17, 1952 

